The field of the present invention is devices and methods for packing cassettes into boxes.
Consumer packaging of magnetic tape has come in recent years to be standardized in a plurality of holders including audio cassettes and three-quarter inch and one inch video cassettes. These cassettes are generally placed in boxes for protection that are intended to remain with the cassette except during playing. To a certain extent the boxes for such cassettes have also been standardized on a relatively few number of styles. One such style is known in the industry as the soft-poly box. This style box is generally made from impact resistant polymeric material and is somewhat flexible. These boxes are also generally made as one piece with a lid hinged along one edge of the box by means of a thin, and therefore highly flexible, integral strip. The lids on such boxes generally include a flange about the front and ends of the lid which extends downwardly toward the box and slightly outwardly thereof. Resilient teeth interlock the lid and the front of the box.
The soft-poly boxes are advantageous in that they are rugged and inexpensive. However, they also exhibit certain drawbacks. Principal among these is the lack of dimensional stability resulting chiefly from the highly flexible nature of the boxes made from the flexible material. The lack of strict dimensional control is of little or no import to the user. However, for the rapid filling of such boxes by a manufacturer, this problem becomes a major difficulty. The boxes are not as easy to hold, index, manipulate the lid, insert the cassette and close the lid as are the more rigid but less durable packaging styles. Difficulties include proper purchase on the lids to insure opening thereof, proper indexing of boxes for positioning to receive cassettes, proper positioning of cassettes within the boxes and proper closure of the lids.
The indexing of boxes is preferably accomplished by having each box push a preceeding box through a loading system. Where individual conveying grippers or stops are required for each box, the speed at which the machine operates is limited. When the items themselves are able to move and index the preceding item, additional speed may be achieved. However, with the soft-poly boxes, two widths exist. The lid is larger than the box itself. Even though this difference is not great, it is sufficient to disrupt indexing for accurate placement of a cassette. The lack of exact dimensional control adds to this difficulty.
Soft-poly boxes also can exhibit a curling of the box sides such that the sides of the box may interfere with the positive placement of a cassette therein. Thus, a force inserting the cassette toward the back of the box may be required as well as a force pushing down on the cassette at the front of the box.
In the handling of cassettes, several devices have been developed. A device for splicing and loading electromagnetic tape onto a cassette is disclosed in U.S. Pat. No. 3,848,825. This patent is incorparated herein by reference to illustrate the sequence of operation of splicing and loading. To further expedite the loading of cassettes, another device was developed which employs automatic threading once the cassette was placed on the spindles of the cassette loading device. This threading mechanism is disclosed in U.S. Pat. No. 4,216,052. The disclosure of this patent is also incorporated herein by reference to particularly illustrate a threading mechanism. A cassette handling device for removing cassettes from a stack, loading the cassettes on a threading machine and then stacking the loaded cassettes in a second pile was also developed. This device is disclosed in U.S. Pat. No. 4,415,301. A device for orienting cassettes which are stacked in alternating directions is disclosed therein. The disclosure of this patent is also incorporated herein by reference to illustrate such cassette handling.